A slight variation on this patch should be sent upstream. I need to add the m4 macro to it for distros that may not have libcap-ng well integrated.
By the way, I think forgot to tell you that you need to also
BuildRequires: libcap-ng-devel and that you will need to add:
touch ChangeLog
autoreconf -i
to the spec file in the %build section (re-opening the bz for this, sorry). If you want, I can attach the patch that would be upstreamed to the bz.